Statistical and clustering analysis of microseismicity from a
Saskatchewan potash mine
Abstract
Typical mining operations can induce microseismicity and in some cases
can result in the occurrence of moderate to large events, which is an
expected but not always fully understood phenomenon. To assess the
safety and efficiency of mining operations, operators must
quantitatively discern between normal and abnormal seismic activity. In
this work, statistical aspects and clustering of induced microseismicity
from a potash mine in Saskatchewan, Canada, are analyzed and quantified.
Specifically, the frequency-magnitude statistics display a rich behavior
that deviates from the standard Gutenberg-Richter scaling for small
magnitudes. To model the magnitude distribution, we consider two
additional models, i.e. the tapered Pareto distribution and a mixture of
the tapered Pareto and Pareto distributions to fit the bi-modal catalog
data. We also observe deviations from the Poisson statistics on
short-time scales that are primarily driven by mining operations. To
study the clustering aspects of the observed microseismicity, the
nearest-neighbor distance (NND) method is applied. This allowed us to
identify characteristics of the clusters of micro-events and to analyze
their structure in space, time and magnitude domains. The implemented
modeling approaches and obtained results can be used to further advance
strategies and protocols for the safe and efficient operation of potash
mines.